Liquid–Liquid Microextraction of Cu²⁺ from Water Using a New Circle Microchannel Device

Abstract

In this work, to evaluate the new circle microchannel device for the removal of Cu2+ from water, various parameters on the mass transfer effect and extraction efficiency were investigated by employing bis(2-ethylhexyl) phosphate (D2EHPA) as an extractant and kerosene as a solvent. The mechanism of Cu2+ extraction from water by D2EHPA(R2H2) is as follows: Cu2+ + 2.1(R2H2)(o) ⇔ (CuR2·2.2RH)(o) + 2H(o)+. The contact time and microchannel diameter were found to have great effect on the volumetric mass transfer coefficient (KLa). However, the temperature, the initial pH of water solution, and the D2EHPA volume fraction of the extraction system nearly had no effect on the KLa. The results of this study revealed that the new circle microchannel may be an effective device for liquid–liquid microextraction as the extraction efficiency for Cu2+ was more than 98% by three stage extraction under optimized conditions.